The police need probable cause or exigent circumstances to enter your home -- CPS does not, and can open an investigation on nothing more than an anonymous tip. On the other hand, the law on leaving children in a vehicle in Nevada is that children under 7 cannot be left alone, and a child of at least age 12 may supervise younger children so long as the 12+ year old is capable of supervising and there are no other safety issues. Hopefully the workers who gave you a hard time have had their moment and won't pursue you or your family.
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CPS is not bound by the same Constitutional protections that bind the police from entry into your some, search & seizure and such because CPS charges are only quasi-criminal.
I agree with my colleagues that no laws were broken here. Child neglect is a gross misdemeanor in Nevada. Be very careful. Leaving a child in a car is a very common scenario where people are charged criminally.
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